Brake



L. E. LA BFWE Oct. 20, 1936.

BRAKE Filed 001;. 2, 1933 2 Sheets-Sheet 2 INVENTOR. lug yer .5. lafirie Q? 61% ATTORNEY Patented Oct. 20, 1936 I BRAKE Lodger E. La Brie, South Bend, Ind., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application October 2, 1933, Serial No. 691,740

12 Claims. (Cl. 188-106) This application is in part a continuation of my in the form shown, includes aright-and-lef t hand copending application 495,809 flied November 15, threaded member seated in correspondingly 1930. It relates to brakes and is illustrated as threaded sockets having slotted bases to embrace embodied in an internal expanding brake oi the the shoe ends.

shiftable anchorage type. The shoes may be held against the adjustment 5 An object of the invention is to provide bal by a tensioned spring 20. Suitable steady rests anced applying means to thrust apart the ends of 22 may be provided for the shoes. this type of brake with equal force. Preferably a flat sided anchor 24 is fixedly se- A further object of the invention is to provide cured to the backing plate (reinforced if necesa fluid cylinder as such balanced applying means, sary, by stamplngs 26) between the shoes, the 10 in combination with means for loading the brake arrangement being such that when the drum is elements constructed and arranged to cooperate turning clockwise the shoe ll anchors therewith the elements of the brake, the anchor and against, while, if the drum is turning counterthe cylinder in maintaining the cylinder norclockwise, the shoe l6 anchors thereagainst.

mally stationary and in maintaining, except on The brake is intended to be applied by either 15 rare occasions, a constant engagement between 01 two controls, viz. a fluid power control for the secondary shoe which carries the fluid power service purposes and a mechanical control for cylinder and the anchor. emergency and parking purposes. Broadly, this In one desirable arrangement a fluid motor is type oi combination of applying means for a 0 carried by the secondary shoe and is arranged to shiitable anchorage brake is disclosed and claimed force the braking elements apart with equal force, in my prior co-pending application 491,589, died the return springs of the brake being constructed October 27, 1930. and arranged to maintain the secondary shoe in The mechanical means is in the form of a floatanchoring engagement until drum contact is eling lever 60 having thrust projections 62 exiected irrespective of the direction of drum rotatending between the shoe ends on opposite sides 25 of the anchor 24. The upper end of the lever is Other objects and features and other novel connected to and actuated by a cable 64 shown desirable constructions will be apparent from the surrounded by a return spring 66. Cable 66 exiollowing description of the illustrated emboditends through an opening in the backing plate ments shown in the accompanying drawings, in and through a Bowden conduit and is connected 30 which: by any suitable means to a hand brake lever.

Figure 1 is a vertical section through the brake The fluid control includes a hydraulic cylinder just inside of the head of the brake drum and I0 bolted rigidlytothe web of the shoe l6 and conshowlng the brake shoes in side elevation; taming a single piston 12 pivotally engaged by Figure 2 is a sectional view taken substantially the rounded end of a piston rod 14. Rod 14 is 35 1311811118 0 Figure slotted across its end to embrace and pivotally Figure 3 is a fragmentary sectional view simiengage the end of the web of shoe I4. I have lar to a portion of Figure 1 and showing a modishown in Figure 1 two return springs 28 and 28a fl d o tensioned between the respective shoes and the Figure 4 is a sectional view taken substantially anchor 24, the lower spring 20a preferably being 40 on the line 44 of Figure 3: stronger than the upper one. The cylinder 10 is Figure 5 is a view similar toFigure 4 showing a provided with cars 16 and I8. Bolts 80 and 82 slight modification; pass through the ears and secure the cylinder Figure 6 is a sectional view taken substantially firmly to the shoe ll. 5 on the line 66 oi Figure 3; In operation the fluid pressure of the motor Figure 7 is a view similar to Figure 3 showing forces the toe of shoe l4 toward the drum, shoe another modification; and i6 remaining anchored by virtue oi the loading Figure 8 is a sectional view taken substantially eii'ect of its relatively strong spring 28". During on the line 8-0 of Figure 7. this lining clearance takeup phase of brake 0p- The brake includes a rotatable drum ill at the eration, the lower portion 01' shoe It also remains 50 open side of which is arranged a support such in contact with the anchor. This is due to the as a backing plate I! and within which is arcontacting contours oi the shoe and anchor. ranged the brake friction means. The latter is With counterclockwise rotation 01 the drum, illustrated as including a pair of shoes ll and l the relative strength of the springs 18 and 28 connected by an adjustable floating joint II which obviates click from the auxiliary shoe ID by maintaining the shoe anchored during the lining clearance takeup. The shoe H in this case is the driving or servo shoe.

It is to be particularly noted that inasmuch as counterclockwise rotation of the drum corresponds to forward motion of the vehicle, the shoe IE is maintained anchored and stationary not only when the brake is released, but also during about 90% of the brake applications. Thus the cylinder Ill is maintained stationary substantially all of the time and the hose leading thereto is substantially free of movement. This type of cylinder with only one piston is advantageous over the conventional type of cylinder with two pistons, in that it is lighter and cheaper and in that it has only one-half of the surface or area liable to leakage of the actuating liquid. Heretofore, it has seemed disadvantageous to use this type of cylinder because of the movement thereof in brake application and consequent bending and wear on the hose supplying liquid thereto. However, when used in combination with a brake of the duo servo type and when secured firmly to the secondary shoe of this brake, the arrangement becomes very efilcient.

In the embodiment shown in Figures 3, 4, and 6, the cylinder l'lfi is provided with a pair of projections IBI which are secured to the shoe H6 by bolts I and I82, the bolts being in line with each other. The cylinder acts through the piston rod I14 on the shoe Ill. The springs I28 are of substantially equal strength and an extra spring I2! is secured to the anchor I24 and the shoe IIG so as to insure that the shoe IN leaves the anchor first in braking, and is always maintained in contact except when carried away from the anchor by the drum llll when the latter is being braked while moving clockwise.

The cylinder III! is provided with an integral boss I'll formed with a bore H3 in which there is normally secured a hydraulic brake fluid hose and the fluid for actuating the brake is supplied through this bore. The boss I ll extends through an oversized hole 3 in the backing plate H2 and thus may shift when the cylinder shifts in reverse braking. The boss I'll is positioned at one end of the cylinder so that the supplied fluid will always enter the cylinder inward oi the piston regardless of the position or the piston.

The alternate means for applying the brakes comprises a lever I64 pivoted at I84 on the shoe I I8 and having a slot I86 formed therein through which there extends a pin lll'l connecting the lever I64 to the strut link I60 which is pivoted to the shoe Ill at I88. A spring I88 (see Figure 4) bearing on the backing plate I I2 and on a washer secured to the inlet projection of the cylinder I10 aids in positioning the cylinder and preventing rattling.

The spring I89 bears at its outer end on a washer I90 fastened to the outer end of the boss Ill and at its inner end on a slidable cover plate IBl which covers the opening H3 in the backing plate H2. The spring and washer not only aid in positioning the cylinder but also maintain the clioger plate Isl in position to cover the opening In the embodiment shown in Figure 5, the cylinder 210 is provided with only a single oflset projection 28I instead of the double projections provided for the cylinder "II and is secured to the shoe 2I5 by bolts 280 and 282 which pass through the shoe H6 and the projection 28L In the modification shown in Figures 7 and 8, the cylinder 310 is provided with a slotted abutment 390 and with a flat face 392 which fit snugly against corresponding portions on the shoe 3H5. The single bolt 380 is therefore sufilcient to hold the cylinder 3T0 securely and rigidly to the shoe 3I6. The piston rod 314 is pivoted to the shoe 3 at 384.

As to the invention shown in Figures 3 to 8 inclusive, this application is subsequent to Taylor application, Serial No. 546,803, but as to the invention shown in Figures 1 and 2 of this application, this application is prior to said Taylor application.

It is to be understood that the above described" embodiments of my invention are for the purpose of illustration only and various changes may be made therein without departing from the spirit and scope of the invention.

I claim:

1. A brake comprising a drum in combination with friction means anchoring at one end when the drum is turning in one direction and at the other end when the drum is turning in the other direction, a floating lever having thrust parts arranged between said ends of the friction means, a cylinder engaging the friction means near one of said ends, and a piston in the cylinder engaging the friction means near the other of said ends.

2. A brake friction device comprising a pair of shoes, 9. cyiinder rigidly mounted on one of said shoes adjacent an end thereof, a piston in the cylinder, a piston rod pivotally engaging the piston at one end and at its other end pivotally engaging an end of the other shoe, together with means within the brake and acting upon the shoes for insuring a constant contact of the shoe carrying the cylinder with the anchor during the lining clearance takeup phase in the application of the brake.

3. A brake friction device comprising a primary shoe and a secondary shoe, a cylinder rigidly mounted on said secondary shoe adjacent an end thereof, a piston in the cylinder, a piston rod pivotally engaging the piston at one end and at its other end pivotally engaging an end of the other shoe, together with means acting upon the shoes for insuring a constant contact of the secondary shoe with the anchor during the lining clearance takeup phase in the application of the brake.

4. A brake comprising a drum, a friction means anchoring at one end when the drum is turning in one direction and at the other end when the drum is turning in the other direction, a spring connecting the ends of said friction members, a second spring secured to one of said ends and to a non-rotating part, and a fluid cylinder secured to one of said ends.

5. A brake comprising a drum, a friction means anchoring at one end when the drum is turningin one direction and at the other end when the drum is turning in the other direction, a spring connecting the ends of said friction members. a second spring secured to one of said ends and to a non-rotating part, and a fluid cylinder secured to the end to which said last named spring is secured.

6. A brake comprising a drum, a friction means anchoring at one end when the drum is turn lng in one direction and at the other end when the drum is turning in the other direction, a cylinder secured to one of said ends, a piston in said cylinder, a piston rod bearing at one end on said piston and at the other end on the end of the friction means opposite to the cylinder, a lever pivoted to the cylinder end of the friction means,

and a strut link having one end in operative connection with the lever and the other end in operative connection with the end of the friction means opposite to the cylinder.

7. A brake comprising a drum, a primary shoe, a secondary shoe, a cylinder secured to the secondary shoe, a lever pivoted to the secondary shoe, a piston in the cylinder, a piston rod operatively connecting the piston and the primary shoe, and a strut link operatively connecting the lever and the primary shoe.

8. A brake comprising a drum, a friction element therein formed adjacent to one end with a pair of flat portions perpendicular to each other, a fluid cylinder formed with a pair of flat portions perpendicular to each other contacting with said friction element fiat portions, and a bolt secursaid cylinder to said element.

9. A brake comprising a drum, a backing plate formed with a slot, a friction element, a fluid cylinder secured to said friction element and having an inlet projection extending through said slot, a washer secured to said projection, and a spring compressed between said washer and said backing plate.

10. A brake for an automotive vehicle comprising a friction device arranged to anchor on one end when the vehicle is moving forward and on the opposite end when the vehicle is moving backward, a cylinder supported by the end of said friction device on which it anchors when the vehicle is moving forward, an anchor between said ends on which the friction device anchors, means holding the end on which the cylinder is supported more strongly against the anchor than said other end, and fluid pressure means in said cylinder which acts on said friction device to apply the brake.

11. A brake comprising a drum, a friction means anchoring at one end when the drum is turning in one direction and at the other end when the drum is turning in the other direction, an anchor pin between said ends, a spring connecting the ends of said friction members, a second spring secured to one 01 said ends and to said anchor pin and a fluid cylinder secured to one said ends.

12. A brake comprising a drum, a friction means anchoring at one end when the drum is turning in one direction and at the other end when the drum is turning in the other direction, an anchor pin between said ends, a spring connecting the ends of said friction members, a second spring secured to one oi. said ends and to said anchor pin and a fluid cylinder secured to the end to which said last named spring is secured.

LUDGER E. LA BRIE. 

